This thread I will be talking like I am pasting this from the Wiki, to elaborate what is th difference between a client side mod and a server plugin. What is a client side mod? A client side mod is where the client (You) on Minecraft sees the world such as a texture pack, graphics, mini-map and so on. These are client side mods, meaning they only work for the client (client being you) so that others will not be able to see them. A good example of this is rei's mini-map, Only the person who has the mod on him can see it, it will not however effect the server in any way. Many client side mods such as "industrial craft" is only for the client (client being you) that is why it will not work on a server. A good representation of a client side mod is you standing in a island dreaming about potatoes, and only you can see the potatoes while the person next to you looks at you strangely. What is a server plugin? A plugin allows you to extend the functionality of the server. You can write plugins that handle extended operations such as authentication requests, server administration, world editing and so on. It also can emulate what the server does, as it represents the world. Such as the plugin “Fiery Inferno” Where it emulates how fires react to combustible material. It can also emulate NPC’s (Squidwards) such as the plugin “Citizens” where some are classed to follow you around the server, others stare at you while you walk by ect. Why cant you add a client side mod to a server like a plugin? I want the Bukkit community to contribute to this question. so fill this out to your hearts content. People who may be interested in answering this question. @Magi1053 @ImminentFate @hawkfalcon @mbaxter @Ne0nx3r0 Is there a way to add a client side mod to a server plugin? Yes, with spout. IF you want to add any additions in the future. just comment them below and ill look at them.